Follower for lubricant pumps



July 23, 1957 H. T. DINKELKAMP FOLLOWER FOR- LUBRICANT PUMPS 2 Sheds-Sheet 1 Filed Nov. 22 1954 [Jillian .514??? 1 I! v VIIIIIIIIIIIIIII'IIIA llllllll INVENTOR IIIIIIIIIIII/VIA I1'I.'IIIIII .July 23, 1957 H. T. DINKELKAMP 2, 0,

FOLLOWER FOR LUBRICANT PUMPS Filed Nov. 22, 1954 r 2 Sheets-Sheet 2 IN VEN TOR.

V azor lze ys United States Patent FOLLQWER FQR LUBRICANT PUMPS Henry 'T. DinltelkammNiles, EL, assignor to Stewart- Warner Corporation, Chicago, Ill., a corporation of Virginia Application November 22, 1954, Serial No. 470,168

15 Claims. (Ct. zen-see This application is a continuation-in-part ofmy copending application Serial No. 126,793, filed November 12,

1949, and now abandoned, for an inventionentitled Follower for Lubricant Pumps) It is common practice in the handling of lubricants for automobile service stations to utilize a pump for removing the contents of barrels .or drums of lubricant, said pump comprising .a long tube extending to the bottom of the drum and having its inlet at the lower end of the tube. .If' the lubricant pumped is a grease, it is highly essential' that. anatmospheric pressure operated follower be employed to prevent cavitation ofthe. grease and to enable the maximum amountflofigreaseto .bepumped from the drum, particularly from the side walls and bottom thereof. Cavitation is Qf disadVantage in that it makes it.possible for thepump to become 1 air-bound so that it will no longer draw in lubricant. Lubricant adhering .to the side walls of the drum and tothe bottom cannot be pumped from the drum but must be removed by hand. I The provision of a satisfactory follower for use in lubricant shipping drums has been diflicult because the open: ings in the tops of thedrums are. usuallyof less diameter than the internal diameter of the drum, so that any follower whichcould be insertedinto the drum was of such small size that it could not contact the side wallsof the drum and, therefore, permitted adherence .to the side walls of substantial quantities of grease. v

One of the other difficulties of such followers was that they were substantially inflexible andleft a .space at the bottom of the drum filled with grease after the travel of the'follower had been terminated. I

It is therefore an object of my invention to provide an improved follower for lubricant pumps, particularly for those used to pump grease from drums in which the. grease is shipped, which may be deformed so as to'be insertable into drums having'openings smaller than the internal or barrel diameter of the drum Which-will nevertheless as.- sume a shape such that thefollower will engage theinternal cylindrical wall of the drum. 7

Another object is'to provide a new and improved follower 'for a lubricant pump which is flexible and winessume a shape'atthejend of its travel such that the grease at the bottom of' the 'dru'm will be forced toward the inlet of the pump and substantially all of the grease i-nthe drum may be removed.

A further object is to provide an improved'follower for grease pumps which with slight alterations may be used with drums of different. internal diameters Still another object is to provide an improved follower for drum pumps which will signal the fact that the drum has been emptied of the fluid contained therein. I

Other objects and advantages will appear from the following description taken in conjunction with the accompanying drawings, in which:

Fig. l is an elevational view, partially broken into section, .of a lubricant pump and drum, showing the follower in an intermediate positionbetween the top and bottom of the drum;

Fig. 2 is a greatly enlarged diametrical sectional view of the follower at the end of its travel and when substantially all. of the grease has been withdrawn from the drum and showing the position in dotted lines;

Fig. 3 is a partial diametrical sectional view of a follower as used for large size drums;

Figs. 4 and 5 are views similar to Fig. 3 but showing the follower modified for use in drums of smaller diameters;

Fig. 6 is a view similar to Fig. 3 and showinga modified form of follower;

'Fig. 7 is a view showing the follower of Fig. 6 moditied for use in drums of smaller diameter and showing how the follower would be used in connection with a pump having an inlet fitting at its lower end of a diameter greater than the diameter of the pump tube; and

Fig. 8 is a view similar to Fig. 5, showing the follower of Fig. 6 modified for use with a still smaller size drum.

Referring to Fig. 1, the invention is illustrated as forming part of a manually operated pump 10 having a tube 12 containing the pump cylinder and piston, the pump being actuated by a suitable pivoted lever handle 14 connected to the pump piston rod 16. The body 18 of the pumpis secured to a plate 'orcover 20 which is removablysecured to the annular top 22 of a grease'shipping drurn24 to close opening25 therein which is shown to be of smaller diameter than the barrel diameter of the drum. At its lower end the pump tube 10 is provided with inlet openings 26 which are close to bottom 28 of the drum 24 to facilitate removal of all of the grease.

A follower 30, the natural or unstressed configuration of which is best seen in Figs. 1 and 3, is slidable on the pump tube 12 and is adapted to lie on top of grease or other fluid 32 contained within the drum and to force it downwardlytoward the bottom of the drum due to the pressure differential existing between the top surface of the follower and the. underside thereof as the pump 10 sucks thegrease from the drum 28. The follower has a generally hollow conical shape and is formed with a hub or axially elongated portion 34 and a relatively thin hollowconical, body disc 36 which is integral with the hub portion 34 and tapers toward its periphery, the body portion.36 being thicker at its central portion than at its periphery. The hub and body portions 34 and 36 are made of a suitable molclable synthetic rubberlike material such, for example, as neoprene which is highly resistant to deterioration by contact with greases and oils. This synthetic material is sufficiently soft so that it may be readily deformed by hand and possesses sufficient resiliency so that it .will .reassume its original and unstressed shape upon release of restraining forces, and, therefore, it can be folded or deformed to be inserted through the opening 25 in the top of the drum 24 and released to assume its full shape and lie on top of the grease 32 and follow it toward the bottomof the drum.

The axially elongated central or hub portion 34 ofthe follower 30 is molded about a metallic sleeve insert 38. which is provided with external ridges40 defining between them a wide groove 42 to provide irregularities which assure a good mechanical bond between the sleeve insert 38 and the rubberlike material of the hub portion 34. The sleeve 38 has a central bore of suchsize as to have a relatively free sliding fit with the pump tube 12 with which it is to be used. Fig. 3 shows that adjacent its upper and lower edges the sleeve 38 is fitted with 0- shaped wiper rings seated grooves 46 in the sleeve.

Patented July 23 1957 These wiper rings provide an adequate seal between the follower and the pump tube 12 to prevent loss of grease or of pump suction. It will also be noted that at the upper and lower edges of the sleeve 33 the rubberlike material of the follower is recessed away from the inner face of the sleeve at 48 so that it does not come in contact with the outer surface of the pump tube 12 and hinder the proper movement of the follower on the tube.

The axial length of the hub portion 34- and sleeve 38 is such as 'to inhibit tilting of the follower on the pump tube 12 due to differences in pressures at the opposite face of the follower, or for other reasons. For example, the grease may-be of non-uniform viscosity due to one side of the drum being raised to a higher temperature than the other by a heat radiator.

At its outer periphery the follower 30 is formed with an annular scraper edge which is relatively thinner than the body portion 36 at the outer edge and also with a plurality of toroidal ribs 52 which are interconnected by portions 54 of substantially thinner cross-section. The annulus 50 is relatively thin so that it may flex upwardly if the follower 30 is used in a drum having a diameter somewhat less than the greatest diameter of the follower 3% including the annular scraper edge 54 When the follower is to be used with drums having an internal diameter approximately equal to that of the outer diameter of the outermost head or rib 5 2, the annulus 5% is severed from the follower leaving the follower somewhat in the shape shown in Fig. 4. Such severance may readily be accomplished by the use of a sharp knife or razor blade. If the follower is to be used with a drum of still smaller size, successive ones of the ribs 52 can be removed as shown in Fig. 5, by cutting through the relatively thinner portion 54 with a knife or razor blade. Thus the follower can be adapted for use with drums having various sizes.

The body of the follower is sufficiently thick that the pressure of atmospheric air upon it will not cause it to collapse and it will remain in substantially the shape shown in Figs. 1, 3, 4 and 5, until it reaches the bottom of the drum. By virtue of the fact that it is of a hollow cone shape, the peripheral edge of the follower may travel the full length of the drum. When the peripheral edge of the follower reaches or strikes the bottom of the drum, the main body of the follower, due to its tapered and conical shape and the fact that it is made from a resilient material, will flex under atmospheric air pressure inwardly from its periphery so as to enable removal of substantially all of the grease from the bottom of the drum. The final shape of the follower is shown in Fig. 2, and it will be observed that underside 56 of the follower is lying substantially flat against the upper surface of the bottom 23 of the drum, and that substantially all of the grease will have been extracted from the drum under the influence of the pump 19. The action of the follower as it flexes at the bottom of the drum is such as to force the grease inwardly toward the pump tube 12 by the pressure differential at its opposite faces.

Inasmuch as the pressure differential between the opposite faces of the follower is greatest at the center of the follower where the pump 10 exerts the greatest suction through the inlets 26, it is preferred that the followerdisc 36 be thickest at that point and that it taper toward a thinner periphery. The taper is such that the flexing of the follower at the drum bottom is controlled and follows the pattern shown in the positions illustrated'in Fig. 2.

Fig. 2 illustrates how the follower signals that the drum 24 is empty. When it reaches the bottom of the drum the axially elongated hub begins to cover the inlet ports 26 and by the time the follower has flexed substantially flat against the drum bottom the lowermost wiper ring 44 will have sealed off the inlets 26 terminating the effective operation of the pump to show that the drum is empty.

A modified form of follower 58 is shown in Figs. 6 to 8 and is slidable on a pump tube 69 provided with an inlet fitting 62 at its lower end having inlet openings 64 therein. The inlet fitting 62 is adjacent the bottom 28 of the drum 24 when the pump is in operative position. The follower 58 is of generally hollow conical shape and is preferably made of a suitable synthetic rubberlike material such, for example, as neoprene. It is provided with an axially elongated hub portion 66 integral with a hollow, conical body portion or disc 68 which tapers toward the periphery of the follower 58, being thicker adjacent the hub portion66 thanat the periphery of the follower. In these respects it is similar to the follower 30.

The axially elongated central or hub portion 66 of the follower is molded about an insert sleeve 70 which is preferably provided with irregularities such as grooves 72 to insure a good mechanical bond between the insert 'lfi and the rubberlike material of the follower 58. The sleeve 70 has a central bore 74 of such size as to have a relatively free sliding fit with the tube 60 of the pump with which it is to be used. Upper flange 76 and lower flange 78 ofthe hub portion are molded with openings of such diameters that these flanges will maintain a sealing and wiping contact with the pump tube 60 to prevent air leaking past the follower (Fig. 7). At its periphery the follower is formed with an annular scraper edge or annulus 80 and generally toroidal ribs 82 and 84 interconnected by an integral portion 86 of thinner cross-section. The annulus 80 is relatively thin and is similar to the annulus 50 so that it may flex upwardly if the follower is used in a drum having a diameter somewhat less than the greatest diameter of the annulus 80, or if it is used in a drum' which has been damaged by being indented.

7 Figs, 7 and 8 show how the annulus 80 and rib 82 may be severed from the body of the follower 5 8 to enable the follower .58 to be used with drums having smaller diameters than the diameter of the largest drum with which the follower is designed to be ,used, as explained in connection with the follower of Figs. 1 to 5.

- In Fig. 7 the action of the follower as it aproaches the bottom of the drum is shown by the dotted line position of the follower at the conclusion of the grease removing operation. Ordinarily the body of the follower is sufliciently thick so that the pressure of atmospheric air upon it will not cause it to collapse but will remain in substantially conical shape until it reaches the bottom of the drum. By virtue of the fact that it has this conical shape, the peripheral edge of the follower will travel the full length of the drum and strike the bottom first. When it does so the main body of the follower, due to its tapered and conical shape will fiex under the atmospheric air pressure inwardly from its peripheral edge so as to enable removal of additional grease, and it will force the grease inwardly toward the fitting 62 and the inlet openings 64 to the pump tube 60. The conical shape of this follower is such that the fitting 62 does not interfere with the removal of nearly all of the grease contained in the drum. It is likely, however, that a small portion may be left and it can be scraped from the bottom of the drum. Howeven'this portion of grease is so small that its removal is not worthwhile and is inconsequential.

t should be clearly understood that the follower 30 may be used with drum pumps provided with the fitting 62 andthat thefollower 58 may be used with drum pumps which have no fittings. It is to be understood, therefore, that these followers are interchangeable.

Because the follower of my invention is constructed of a flexible rubberlike material, it may be used with a large variety of drums having different size openings, being deformed to be inserted through openings having a diameter smaller than the barrel diameter of the drum. By virtue of the shape of the peripheral edge portion of the follower whereby annular parts may be readily sever'ed, the follower readily adaptcdto drums of various diameters. Due to the conicalshape' ofthe follower andits tapered cross-section and that it is made of-flexible material, it will function to remove substantially all "of the grease contained in the drum whether the follower be used on drum pumps provided with a fitting' 62 or ondrum pumps which have no such fittings.

The flexibility of the follower also insures that it will function satisfactorily in drums which are dented or otherwise damaged so that they do not have a smooth cylindrical internal surface. When the follower is to be used. with drums having corrugations in the side walls, it willbe found desirable to have abo'utgone-eighth' inch clearance between the follower and the wallet the drum was to make certain the follower will pass such corrugations. Even when;allowing such clearance, it will be found that very little grease will 'adhere to the side walls ofthedrum i j While Ihave' shown and described two preferred embodiments of my invention, it will be apparent that numerous variations and, modifications 1 thereof may be made witho d p rting f m the :uuderlying principles of the. invention. 1, therefore, desireby. the followingclaims to includewithin thescope of thejinvention allsuch variations-and modifications I by, which substantially the results of rny {invention may be obtained'through the use of substantia'lly the sam e or equivalent means.

I claim:

1. For use with a pump employed to remove viscous materials from shipping drums, a follower of generally conical shape made of a pliable resilient moldable composition which is resistant to deterioration by contact with grease, said follower having a metallic sleeve insert having a sliding fit relative to a tubular portion of the pump with which it is to be used, said'moldable composition substantialy enclosing said sleeve insert and the follower being otherwise unsupported between said insert and the periphery of the follower.

2. For use with a pump employed to remove viscous materials from shipping drums, a follower of generally conical shape made of a pliable resilient moldable composition which is resistant to deterioration by contact with grease, said follower having a metallic sleeve insert having a sliding fit relative to a tubular portion of the pump with which it is to be used, said moldable composition substantially enclosing said sleeve insert, said sleeve insert being formed with a pair of axially spaced internal grooves, and wiper rings retained in said grooves to slide on the surface of the tubular portion of the 7 pump.

3. For use with a pump employed to remove viscous materials from shipping drums, a follower of generally conical shape made of a pliable resilient moldable composition which is resistant to deterioration by contact with grease, said follower having a metallic sleeve insert for engagement with a tubular portion of the pump with which it is to be used and having an apertured central portion providing flanges extending beyond the ends of the sleeve insert for engaging this tubular portion of the pump.

4. The combination set forth in claim 3 in which the peripheral edge portion of the follower is formed by annular parts which may be readily severed from the body of the follower to reduce its diameter for conditioning the follower for use with drums of smaller diameter.

5. For use with a pump employed to remove viscous materials from shipping drums and having a tubular pump portion, a follower of generally hollow conical shape made of a pliable resilient composition which tapers in thickness from its central portion toward its periphery, said follower having an apertured central portion for sliding engagement with the tubular portion of the pump.

6. For use with a pump employed to pump viscous materials. from shipping drums, an atmospheric air pressure-.operatedfollower disc made of a pliable resilient Y composition which is resistant to deterioration by contact; with grease, said follower disc having an apertured ce'ntraLportion for engagement with a tubular portion of the. pump with which the follower is to be used and having a peripheral edge portion formed by integral annular concentric ribsinterconnected by a part of reduced thickness to facilitatefsevering the outermost ribs from the follower disc to reduce the eifectivediameter of, the follower disc for conditioning the follower for use with drums of smaller-diameter.

, 7. Foruse with a pump having a tubular portion adapted to be inserted into a drum or the like to pump viscous fluid therefrom, a flexible follower for assuring substantially; complete removal of fluid from the drum and comprising in combination a sleeve insert slidable on the tubular pump'portion, a central portion enclosing said sleeve insert to be slidable therewith, a relatively thin body disc of generally'conical shape integral with and extendingradially from said central portion, a circular scraper edge integral with said body disc at the periphery of the follower and said body disc, together with the .edge thereofand said central portion being formed of a resilient material whereby the follower may be inserted into a drum having an opening smaller than the drum diameter.

8. For use with a pump having a tubular portion insertable into shipping drums and the like for pumping viscous fluid therefrom, a follower adapted to be inserted repeatedly into drums having openings therein substantially smaller diametrically than the follower and comprising in combination, an apertured central portion adapted to encircle the tubular pump portion for a free sliding movement thereon, a body disc of resilient grease resistant material extending radially from said central portion, said body disc having a generally conical shape and a circular scraper edge integrally formed on said body disc at the outer periphery of the follower.

9. For use with a pump having an elongated portion adapted to pump viscous fluid from shipping drums and the, like, a flexible follower of a resilient material adapted ,to assure substantially complete emptying of a drum by the pump and comprising in combination a central portion apertured to slidably encircle the elongated pump portion, a relatively thin body disc of resilient material extending radially from said central portion, a plurality of concentric annular portions of different thicknesses integral with said body disc at the outer periphery of the follower and each of said annular portions being connected to the adjacent radially inward annular portion by a relatively thinner part to facilitate severing the outer annular portion from the adjacent radially inward annular portion to reduce the effective diameter of the follower for use in drums having smaller diameters.

10. For use with a pump employed to remove viscous materials from shipping drums, an atmospheric air pressure operated follower having a generally circular periphery and having an apertured central portion for sliding engagement with a tubular portion of the pump with which it is to be used, said follower havinga relatively thin body discformed integrally with the central portion and tapering in thickness from the central portion toward the periphery so that the periphery of the follower is thinner than the portion thereof adjacent said central portion, and said follower being made of a resilient composition which is resistant to deterioration by contact with grease so that said follower may be manually deformed to enable it to be inserted into a drum having an opening smaller than its barrel diameter.

11. For use with a pump employed to remove viscous materials from shipping drums, an atmospheric air pressure operated follower of hollow conical shape made of a resilient composition which is resistant to deterioration by central portion for sliding engagement with a tubular portion of the pump, said follower having a hollow conical body formed integrally with the central portion and tapering in thickness from the central portion toward its periphery whereby as said follower approaches the bottom of the drum it Will flex to enable a pump to remove the viscous material enclosed Within the hollow conical body.

12, The combination set forth in claim 11, in which said central portion is axially elongated to resist tilting of said follower due to pressure differences between the opposite faces thereof.

13. A pump for pumping'viscous fluid from shipping drums and the like and having a tubular portion and follower means for assuring the substantially complete removal of lubricant from each drum by the pump and including a central portion freely slidable along said tubular pump portion, and a body portion of pliable rubberlike resilient material extending radially from said central portion, said body portion having a hollow conical shape and a cross sectional thickness tapering from said central portion toward the periphery of the follower.

l4. A pump having an elongated tube for pumping viscous fluid from shipping drums and the like, said tube being insertable into the drum and having an inlet formed in its wall at its lower end, and a follower for assuring substantially complete emptying of each drum and including an elongated central portion apertured to slidably encircle said tube, and a relatively thin body of hollow conical shape formed'fnor'n aflexible resilient material and extending radially from said central porti-on,-said body flexing under the pressure differential art-opposite faces of saidfollow'er when said follower has reached the bottom of the drum to force the viscous fluid towardsaid'tnbe and said inlet, and'said elongate'dcentral portion covering said inlet to stopioperation of the pump Whenuthe drum has been emptied.

15. For use with a pump employed to remove viscous materials from shipping drums and having a tubular pump portion, a follower of generally hollow conical shape made of a pliable resilient composition which tapers in thickness from its central portion toward its periphery, said follower having an apertured central portionfor sliding engagement with the tubular portion of the pump, and a circular scraper edge of a resilient material integrally formed at the outer periphery of the conical shape.

References Cited in the file of this patent UNITED STATES PATENTS Sundholm a Nov. 24,1953 

